public class Accound{
    //成员变量
    private String id;//卡号
    private double balance;//余额
    private String type;//类型

    public void setId(String id){
        this.id=id;
    }
    public String getId(){
        return id;
    }

    public void setBalance(double balance){
        this.balance=balance;
    }
      public double getBalance(){
        return balance;
    }
    public void setType(String type){
        this.type=type;

    }
    public String getType(){
        return type;
    }
     public Account(){
       System.out.println("调用了");
    }
     public Account(String id,double balance){
       System.out.println("调用了");
        this.id=id;
        this.balance=balance; 
    }
    public Account(String id,double balance,String type){
        this(id,balance);
         //和下面一样
        // this.id=id;
        // this.balance=balance;
        this.type=type;
        System.out.println("调用了");
    }
}